If dithering is enabled, the remainder of the soft_pwm_X duty value at
turnoff time is added to the next cycle. If e.g. the duty is set to 9 and
SCALE is set to 2, the PWM will be active for 8 counts for 3 cycles and
12 counts on each fourth cycle, i.e. the average is 9 cycles.
This compensates the resolution loss at higher scales and allows running
fans with SOFT_PWM with significantly reduced noise.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
A 128 step PWM has 127 intervals (0/127 ... 127/127 duty). Currently, a
PWM setting of 1/127 is active for 2/128, i.e. double the expected time,
or, in general n+1/128 instead of n/127.
Fixes issue#6003.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Stefan Brüns